President Trump on Wednesday addressed injuries suffered by U.S. troops in Iran’s recent ballistic missile attacks in Iraq, saying that he can report “it is not very serious” and that defense officials told him about them days after the fact.

“I heard that they had headaches and a couple of other things,” the president said. “But I would say, and I can report, it is not very serious, not very serious.”

The comments came after the Pentagon acknowledged Tuesday evening that more U.S. service members have been removed from Iraq for treatment and testing after experiencing concussion-like symptoms caused by the Jan. 8 attack on al-Asad air base in Iraq in which 11 ballistic missiles caused massive explosions and deep craters and left charred wreckage.

Trump and defense officials initially said that no one was injured, but the Pentagon reported last week that 11 service members had been flown out of Iraq to receive follow-up treatment. Defense officials said Tuesday that even more had left, but they declined to say how many or to address questions about whether anyone has been sent back to the United States or been returned to duty.

Air Force Maj. Gen. Alex Grynkewich, a senior commander for the U.S. mission in Iraq and Syria, told reporters outside Washington on Wednesday that he thinks the number of service members who will need treatment is “in the teens.” He said that they were “looked at for TBI,” an acronym for traumatic brain injury that can range from a mild concussion to something more serious.

“I don’t actually have an update on the severity of the injuries,” Grynkewich said, citing his time traveling out of Iraq over the past week. He said that some of the service members had been taken to Landstuhl Regional Medical Center in Germany, “and we’ll do whatever we need to to take care of those soldiers or airmen.”

The general said later in the day at the Pentagon that he visited al-Asad and found that in one case, a service member was in a bunker tens of meters from where a missile hit. He said the missile knocked over a “T-wall,” a hulking concrete barrier designed to protect service members from enemy fire.

“It knocks over the T-wall onto the bunker and there was someone in that bunker,” he said. “I didn’t measure it, but not that far away.”

Trump, speaking in Davos, Switzerland, said that journalists would “have to ask the Department of Defense” about whether possible traumatic brain injuries were serious. Then he said that he did not think they were, “relative to other injuries that I’ve seen.”

“I’ve seen what Iran has done with their roadside bombs to our troops,” Trump continued. “I’ve seen people with no legs and with no arms. I’ve seen people that were horribly, horribly injured in that area, that war.”

The Pentagon considers TBI to be a signature wound of the wars in Iraq, Afghanistan and Syria and acknowledges that some can be debilitating. More than 313,800 service members have suffered such injuries in combat or training, according to a Defense Department fact sheet. Symptoms do not always manifest themselves immediately and can include blurry vision, slurred speech and headaches.

Grynkewich, when asked about Trump’s comments about TBI and what message they send, said he had not heard them.

“I haven’t seen his remarks, and even if I had, I wouldn’t comment on them,” he said.

He added that TBIs are difficult to assess and that there was “certainly no influence from anyone outside the military in how we can talk about that or should we talk about it.”

The discussion has dogged senior U.S. officials after initial reports that no one was injured in the attack, launched in retaliation for the United States’ killing of Iranian military commander Qasem Soleimani, who had been linked to the deaths of hundreds of U.S. troops over the past 20 years.

Trump tweeted “All is well!” the night of the Jan. 8 attack. He doubled down on that the following morning in remarks at the White House while flanked by the members of the Joint Chiefs of Staff.

“No Americans were harmed in last night’s attack by the Iranian regime,” Trump said. “We suffered no casualties. All of our soldiers are safe, and only minimal damage was sustained at our military bases.”

Jonathan Hoffman, the chief Pentagon spokesman, said last week that Trump’s comments at the time were based on initial reports the Pentagon had received. Initial reporting, he said, focused on whether anyone had lost their life, a limb or eyesight.

“They all walked onto the aircraft under their own power to assess whether they have a traumatic brain injury,” Hoffman said.

U.S. military officials acknowledged the possibility of brain injuries within days of the attack, as a handful of reporters visited al-Asad on Jan. 13. A military official said at the time that “dozens” of service members were suffering from concussion-like symptoms.

Trump, asked whether he could explain the discrepancy between initial reporting and the latest injury updates, said he could not. That information was passed to defense officials in Washington on Jan. 15, after a second wave of service members left Iraq, Hoffman said last week.

The U.S. military’s future in Iraq remains unclear after the suspension of most joint operations against the Islamic State in the aftermath of the strike on Soleimani.

Grynkewich said Wednesday that it is “difficult to say exactly what the right word is to describe” current interactions between the two militaries.

The United States would like to collaborate on operations in the future, but that will depend on discussions between U.S. and Iraqi officials, he said.

Asked what will happen if the Iraqi government asks the United States to leave, he answered cautiously.

“I actually don’t want to get into that hypothetical,” he said.